After you file

Since you're using TurboTax Desktop edition (CD/Download), you can access that question using the Forms Mode.  You'll see the option to switch to Forms Mode in the upper right-hand side of your screen.

Once you've done that, you'll see all of the forms currently in your return listed on the left-hand side of your screen.  At the top of the list should be your Form 1040.  Click on that form, then manually change the entry on the form.  I'm sharing a screenshot of the form and where the question is asked.